The Yale Police union voted unanimously Thursday to join the Connecticut Organization for Public Safety Employees, a larger and more powerful parent union.

All 50 attending members of the union, the Yale Police Benevolent Association, agreed to combine forces with COPS. The decision was prompted by concerns with Police Chief James Perrotti’s leadership style and by communication breakdowns with the department’s management.

Five YPBA members did not attend the vote.

Yale police are not legally permitted to join an AFL-CIO union, but COPS, established last year by retired Connecticut police officers, would provide the Yale Police with greater legal leverage in dealing with department management. Christopher Morganti, YPBA steward and a Yale Police Department officer, said the move would give Yale police more flexibility in addressing grievances.

“Historically, our union files grievances when necessary and we’ve only been able to take the most serious ones to the last step,” Morganti said. “Now we should be able to take almost all our grievances to an arbitrator.”

Morganti said difficulties with YPD management reached the breaking point in the Feb. 4 arrest of East Windsor police officer Rafael Crespo. According to the YPBA, the police officers who arrested Crespo on a charge of kidnapping and sexual assault were not informed of violent threats Crespo had made against police.

COPS Executive Director Ron Suraci said the move would widen the YPBA’s resources in negotiating with management, providing legal representation and training to YPBA members.

“It’s very exciting news,” Suraci said. “The outcome of the election was tremendous — you can’t hope for better than that. I think we’re both looking forward to working with each other.”

The YPBA sent a letter to Yale University Secretary Linda Lorimer March 1 expressing dissatisfaction with department management for withholding crucial information and requesting that Yale initiate an independent investigation of the Crespo case.

Martha Highsmith, Yale’s deputy secretary, said Lorimer was looking into the YPBA’s letter and would act as she saw fit.

Meanwhile, the YPBA contacted COPS to discuss possible membership, a move resulting from disagreements over disciplinary actions and terminations, as well as the Crespo case controversy. Thirty YPBA members last week attended a COPS presentation that both parties described as productive and promising for a future relationship.

Highsmith said in her 10 years of experience she had not heard of any desire on the part of the YPBA to join a parent union, but she said she respected the move as a union decision.