Using the same jar in different modules in Android Studio

I have an app using many modules such as facebookSDK, linkedInSDK etc. I needed to add one more module that is using volley library which is also used in linkedInSDK.

It builds successfully but causes:

Error:Execution failed for task ':splashActivity:dexDebug'.
> com.android.ide.common.process.ProcessException: org.gradle.process.internal.ExecException: Process 'command 'C:\Program Files\Java\jdk1.8.0_31\bin\java.exe'' finished with non-zero exit value 2

this error.

app build.gradle:

compile(name: 'app-debug', ext: 'aar')
compile 'com.android.support:support-v4:22.2.0'
compile 'com.mcxiaoke.volley:library:1.0.17@aar'
compile 'com.android.support:appcompat-v7:22.2.0'

linkedInSDK build.gradle:

compile 'com.android.support:support-v4:18.0.0'
compile files('libs/volley.jar')

As you can see, they both use volley library. When I remove one of them it throws cannot be resolved error in that module.

Any suggestions?