Question: Vibulenus Agrippa was accused of treason under the reign of the Emperor who was leader during which years?

Context paragraphs:
Pei Yan: Pei Yan (裴炎) (died November 30, 684), courtesy name Zilong (子隆), was an official of the Chinese dynasty Tang Dynasty, serving as a chancellor during the reign of Emperor Gaozong, as well as regency by his wife Empress Wu (later known as Wu Zetian) over their sons Emperor Zhongzong and Emperor Ruizong.  He was well trusted by Emperor Gaozong and Empress Wu late in Emperor Gaozong's reign, but drew Empress Wu's ire after he advised her, then empress dowager, to end her regency and return power to Emperor Ruizong.  In 684, she accused him of treason and executed him.

Vibulenus Agrippa: Vibulenus Agrippa (called Vibullius Agrippa in Dio's "Roman History") was a Roman knight of the Equestrian rank who was accused of some crime, probably treason, before the senate in the final years of the reign of Tiberius, in 36 AD.  His case is often mentioned to highlight the frequency with which ordinary citizens were being executed in that time, and for the novelty of the case's outcome: Vibulenus faced his accusers in the senate and swallowed poison that he had brought with him in a ring.

Li Zi: Li Zi (李滋) (died 897), formally the Prince of Tong (通王), was an imperial prince of the Chinese dynasty Tang Dynasty.  He was the favorite son of Emperor Xuānzong, but was unable to take the throne after Emperor Xuānzong's death, as his older brother Li Wen (Emperor Yizong) was chosen by the eunuch Wang Zongshi (王宗實), who overpowered other eunuchs who supported Li Zi.  Later, during the reign of Emperor Yizong's son (Li Zi's nephew) Emperor Zhaozong, Emperor Zhaozong tried to commission imperial princes to command armies to counteract the powerful warlords ("Jiedushi") and eunuchs.  In response, in 897, when Emperor Zhaozong had to flee to the domain of one of the warlords, Han Jian, Han falsely accused 11 imperial princes, including Li Zi, of treason, and massacred them without approval from Emperor Zhaozong.

Cen Changqian: Cen Changqian (; died November 7, 691), briefly known as Wu Changqian (武長倩) during the reign of Wu Zetian, formally the Duke of Deng (鄧公), was an official of the Chinese dynasty Tang Dynasty and Wu Zetian's Zhou Dynasty, serving as chancellor during the reign of Emperor Gaozong, as well as Wu Zetian's reign and her earlier regency over her sons Emperor Zhongzong and Emperor Ruizong.  In 691, he offended Wu Zetian by opposing the movement to declare her nephew Wu Chengsi crown prince (thus displacing the former Emperor Ruizong, whom she demoted to crown prince status in 690 after taking the throne herself), and he, along with his fellow chancellors Ge Fuyuan and Ouyang Tong, were accused of treason and executed.

Pons Agrippae: The Pons Agrippae (Bridge of Agrippa) was an ancient bridge across the River Tiber in Rome.  It was located 160 metres above the Ponte Sisto, and is known from an inscribed cippus set up by the curatores riparum during the Principate of the Emperor Claudius, suggesting it was built during or before the reign of Claudius.  It was restored in 147 AD.  The bridge is named after Marcus Vipsanius Agrippa, a close friend of the Emperor Augustus.  Agrippa married Julia, the daughter of Augustus, and the couple lived in a villa on the opposite bank of the River Tiber.  To connect his villa to the Field of Mars, where Agrippa had built several important monuments, it has been suggested that Agrippa constructed the Pons Agrippae.

Vipsania Polla: Vipsania Polla was the daughter of Lucius Vipsanius Agrippa (a man of equestrian rank) and sister to another Lucius Vipsanius Agrippa, as well as the Roman general and politician Marcus Vipsanius Agrippa.  Polla lived during the late Roman Republic and during the reign of Rome's first Emperor Augustus.

Decimus Haterius Agrippa: Decimus or Didius Haterius Agrippa was the son of the orator and senator Quintus Haterius.  He was tribune of the plebs in AD 15 and vetoed proposals; was praetor in 17, consul in 22, and senator from 15 on.  Agrippa at one time strongly urged the emperor Tiberius to nominate a limited number of political candidates from each family.  He died in 32, a victim of Tiberius' reign of terror.  He is not to be confused with Postumus Agrippa, a kinsman (half-uncle).

Shangguan Yi: Shangguan Yi (; 608 – 4 January 665), courtesy name Youshao (游韶), formally Duke of Chu (楚公), was an official of the Chinese dynasty Tang Dynasty, serving as chancellor during the reign of Emperor Gaozong.  In 664, with Emperor Gaozong displeased with his wife Empress Wu (later known as Wu Zetian) for her controlling behavior, Shangguan proposed that Empress Wu be deposed, a proposal that Emperor Gaozong was initially receptive to but disavowed once Empress Wu discovered it.  Empress Wu then had Shangguan accused of plotting treason with Emperor Gaozong's oldest son, the former crown prince Li Zhong (who had been displaced by Empress Wu's son Li Hong), and Shangguan was executed.  His granddaughter Shangguan Wan'er later served as a key secretary to Empress Wu and a concubine to her son Emperor Zhongzong.

Zhangsun Wuji: Zhangsun Wuji (died 659), courtesy name Fuji, formally the Duke of Zhao (趙公 ), was a Chinese official who served as a chancellor in the early Tang dynasty.  He was Empress Zhangsun's brother, which made him a brother-in-law of Emperor Taizong (Li Shimin) and a maternal uncle of Emperor Gaozong (Li Zhi).  He was an important advisor to Li Shimin when the latter was still the Prince of Qin during the reign of his father, Emperor Gaozu.  He helped Li Shimin overcome his brothers Li Jiancheng (the Crown Prince) and Li Yuanji (the Prince of Qi) in a succession struggle at the Xuanwu Gate Incident, eventually enabling Li Shimin to become the heir apparent and later the emperor.  He was also instrumental in Emperor Taizong's selection of Li Zhi as the Crown Prince, and was exceedingly powerful after Li Zhi took the throne as Emperor Gaozong.  However, he gradually fell out of his nephew's favour by failing to support Emperor Gaozong's decision to depose his first wife, Empress Wang, and replacing her with Empress Wu.  In 659, Zhangsun Wuji was falsely accused of treason by Empress Wu's political ally, Xu Jingzong, and eventually ordered to be sent into exile by Emperor Gaozong.  Xu Jingzong subsequently sent the official Yuan Gongyu (袁公瑜) to force Zhangsun Wuji to commit suicide on his way to exile.

Tiberius: Tiberius (Latin: "Tiberius Caesar Dīvī Augustī Fīlius Augustus" ; 16 November 42 BC – 16 March 37 AD) was a Roman emperor from 14 AD to 37 AD.  Born Tiberius Claudius Nero, a Claudian, Tiberius was the son of Tiberius Claudius Nero and Livia Drusilla.  His mother divorced Nero and married Octavian, later known as Augustus, in 39 BC, making him a step-son of Octavian.

Supporting paragraphs: Vibulenus Agrippa Tiberius
Answer: 14 AD to 37 AD