CERTIFICATION                                                       Exhibit 31.1

I, Martin A. Roenigk, certify that:

1.   I  have  reviewed  this   quarterly   report  on  Form  10-Q  of  CompuDyne
Corporation;

2.   Based on my knowledge, this report does not contain any untrue statement of
a  material  fact  or omit  to  state a  material  fact  necessary  to make  the
statements made, in light of the circumstances  under which such statements were
made, not misleading with respect to the period covered by this report;

3.   Based on my  knowledge,  the  financial  statements,  and  other  financial
information included in this report, fairly present in all material respects the
financial  condition,  results of operations and cash flows of the registrant as
of, and for, the period presented in this report;

4.   The  registrant's  other  certifying  officer  and I, are  responsible  for
establishing and maintaining  disclosure  controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal  control over financial
reporting  (as defined in Exchange Act Rules  13a-15(f) and  15d-15(f))  for the
registrant and have:

     (a)  Designed  such  disclosure  controls  and  procedures,  or caused such
disclosure  controls and  procedures to be designed  under our  supervision,  to
ensure that  material  information  relating to the  registrant,  including  its
consolidated subsidiaries,  is made known to us by others within those entities,
particularly during the period in which this report is being prepared;

     (b) Designed such internal control over financial reporting, or caused such
internal control over financial  reporting to be designed under our supervision,
to provide reasonable assurance regarding the reliability of financial reporting
and the preparation of financial  statements for external purposes in accordance
with generally accepted accounting principles;

     (c) Evaluated the effectiveness of the registrant's disclosure controls and
procedures and presented in this report our conclusions  about the effectiveness
of the disclosure  controls and procedures,  as of the end of the period covered
by this report based on such evaluation; and

     (d)  Disclosed  in this  report  any  change in the  registrant's  internal
control over financial  reporting  that occurred  during the  registrant's  most
recent fiscal quarter that has materially  affected,  or is reasonably likely to
materially affect, the registrant's  internal control over financial  reporting;
and

5.   The registrant's  other certifying  officer and I have disclosed,  based on
our most recent evaluation of internal control over financial reporting,  to the
registrant's   auditors  and  the  audit  committee  of  registrant's  board  of
directors:

     (a) All significant  deficiencies and material  weaknesses in the design or
operation of internal  controls over  financial  reporting  which are reasonably
likely  to  adversely  affect  the  registrant's  ability  to  record,  process,
summarize and report financial information; and

     (b) Any fraud,  whether or not material,  that involves management or other
employees who have a significant role in the registrant's  internal control over
financial reporting.

     Date: August 9, 2005

                                                    /s/ Martin Roenigk
                                                    ------------------
                                                    Martin Roenigk
                                                    Chief Executive Officer


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