American Sign Language is the first language of many deaf people in the United States, according to 2013 information from the North Carolina Department of Health and Human Services. Speech-language pathologists are not required to learn ASL, even though some of their training covers working with people who are deaf or who have hearing impairments. However, many choose to learn the language, as fluency brings benefits in both clinical practice and career terms.

Achieving Linguistic Competence

According to the American Speech-Language-Hearing Association, linguistic competence plays a vital role in effective speech pathology, and a pathologist should consider a client's primary mode of communication before he can propose therapies. Pathologists with proficiency in ASL have an advantage when working with ASL-signing clients, as they share a communication platform. Fluency also enables them to make initial assessments of ASL users. Many environments, such as education services, now require that assessments use the language in which individuals communicate.

Improving Communication with ASL Users

Speech-language pathologists who have learned ASL may be able to build stronger relationships with clients who use the language. According to ASHA, pathologists who can sign show respect and sensitivity toward their clients. Fluency may also improve communication with members of a client's family who sign. Pathologists who don't have any fluency in ASL may have to use interpreters during therapy sessions, which may dull some of the advantages of direct communication.

Using ASL as a Therapy Tool

ASL is an augmentative and alternative communication tool that gives people alternative methods of communication to speech. Signing fluency enables speech pathologists to help some clients who cannot communicate orally. This may give a temporary or permanent solution to a problem. For example, children with apraxia have the ability to make the sounds of speech but have difficulty doing so. In some cases, a child may find learning to sign first helpful, giving her a mode of communication she can use in later oral therapies.

Improving Job Prospects

Speech-language pathologists who learn ASL may be more attractive to employers, as they effectively have fluency in a second language. This opens opportunities to work with deaf and hearing-impaired clients or people who might benefit from learning to sign as part of their therapy. Some public school systems require speech-language pathologists to have a second language, which can include ASL, before they can work in the system.