Department Faculty and Staff

Public Services Department

Carlos Wittke, Department Chair
575-527-7746 –

Argie Hernandez, Division Advisor
575-528-7403 –

Heather Grenci, Administrative Assistant, Associate
575-528-7640 –

Criminal Justice and Law Enforcement Program Faculty


Carlos Wittke, MCJ

 J Wittke

Mr. Juan Carlos Wittke is the Department Chair for the Public Services Department at Dona Ana Community College. He holds a Masters Degree in Criminal Justice Administration from Sul Ross State University. Mr. Wittke is retired from the El Paso County Sheriff's Office where his last position there was a Deputy Lieutenant. Mr. Wittke has worked in almost every section of the Sheriff's Office. Mr. Wittke has also been an adjunct professor at the University of Texas El Paso since 2012 teaching in the Criminal Justice Department.


Robert J. Perez Sr., MCJ 

A portrait of Robert J. Perez Sr.

My name is Robert J. Perez Sr. and I am a Criminal Justice Instructor here at DACC/NMSU.  I was out of the area for over 20 years working in the law enforcement field.  In 2013, I ended that chapter in life and returned to my old stomping grounds, here in Las Cruces, NM.  I grew up in the Mesilla area and attended Las Cruces High School, graduating in 1987.  I immediately started college at NMSU and graduated with a Bachelor in Criminal Justice in 1992.

After that, I went on to become a police officer and Sheriff’s Deputy in the Four Corners Area of New Mexico.  I worked in or with every aspect of the Law Enforcement function at my agency as well as partnered with outside agencies both local and Federal from all over the country.  My desire was always to be a detective and eventually with hard work and perseverance, I obtained the rank of Detective in 1999.  I was later promoted to the rank of Det. Corporal, then Det. Sergeant and was the only individual at the time to have earned advanced rank while remaining within the division.  During that time, I also went back to school and in 2004, earned a Master’s Degree in Criminal Justice from Boston University. 

Specializing in Major Case Investigations and Death Investigations, I was a taskforce member with Federal and State teams investigating child pornography/exploitation as well as taskforce teams with Region II Narcotics and San Juan County violent crime investigations.  Over the years, I was part of hundreds of investigations in the combined areas of; White Collar Crimes, Property Crimes, Computer Crimes, Crimes Against Children and Elderly, Domestic Violence, Sex Crimes, Death Investigation and Homicide.  I supervised numerous detectives, crime scene technicians and civilians within the Detective Bureau and instructed at both the Police Training Academy and Civilian Academy in the areas of Interview and Interrogation, Domestic Violence, Investigations and Police Operations. 

I am now retired and I've been given a great opportunity here at DACC to pass on what I have learned and experienced over a 20-year Law Enforcement career. It's an amazing job, but it is not for everyone.  Honestly, I feel it's a special privilege to be able to instruct in the field of Law Enforcement as well as to stay connected to the profession I love.  It's equally a privilege to have the opportunity to give back to the community.